1. Field of the Invention
The present invention generally relates to a stereo-image displaying technology, in particular, to a stereo-image displaying apparatus and a method for reducing stereo-image cross-talk.
2. Description of Related Art
The three-dimensional (3D) displaying manner has stepped into a commercialization stage as the vigorous development of the displays. It is a common understanding in this industry that 3D displaying apparatus certainly will become an important developing direction for displays in the next generation. More and more markets, for example, medicine, exhibition, entertainment, education, military, design, and advertisement etc., need the naked-eye 3D displaying technology.
However, the 3D displaying technology still encounters various obstacles, as it has gradually become prevailing. One of the largest obstacles still lies in the limitation of the displaying technology itself. Currently, one of the main bottlenecks of the 3D display commercialization is that, the image quality cannot satisfy the users' demands in the aspects of, for example, viewing angle, and number of the viewers, as compared with the 2D display. The problem most distinctly affected the 3D displaying effect is a cross-talk between stereo-images. In the 3D technology, the image quality has not been significantly improved, and particularly, no effective solving method is proposed for the cross-talk problem that most seriously affects the eye vision.
The cross talk index is listed as a basic parameter of the 3D displaying apparatus. The ghost problem resulted from the cross-talk is always an important topic in the research of the 3D displaying apparatus. In time-multiplex 3D displaying apparatus, mostly the response speed of the displaying apparatus is not sufficiently high. Currently, the main stream 2D displaying apparatus is liquid crystal display (LCD) device, and the LCD device, as a non-self-luminous display, has different response characteristics compared with the self-luminous display in the past, for example, CRT display. Particularly, as the requirement for the response speed of the stereo-image is usually 2 times or even higher than that for the common display device, no matter how fast the speed of the 2D display has developed, an even higher response speed is required in the 3D applications. As the 3D displaying technology has a higher requirement for the reaction speed, the cross-talk problem for the left and right eyes becomes increasingly serious.
As for the 3D displaying technology, in accordance with the vision characteristics of human eyes, when two images with different parallaxes are respectively viewed with the left and right eyes, a stereo-image is formed. However, if the reaction speed for the image displaying is not sufficiently high, for example, some image of the left eye is residual for the right eye during the switching, and vise versa. In this manner, the so-called ghost image is generated, that is, when viewing the image of the left eye, the left eye views another overlapped weak image at the same time, which is the image of the previous image frame for the right eye. FIG. 1 is a schematic view of a conventional image cross-talk phenomenon. In FIG. 1, under the ideal state (on the left part of the figure), for example, an image signal 100 is an image for the left eye, and an image signal 102 is an image for the right eye. Under this situation, the display only displays the image content of the right eye. However, if the image cross-talk phenomenon occurs (on the right part of the figure), the display displays the image of the left eye and a previously residual image 104 of the right eye at the same time, and similarly, the right eye may view the residual image 106 of the left eye.
In order to solve the above cross-talk problem, an image processing manner is adopted in the conventional art. That is, the cross-talk intensity of the 3D display is removed in the image before hand, and thus, when the cross-talk is generated during the actual viewing process, the removed image intensity can be compensated. FIG. 2 is a schematic view of a mechanism of improving the cross-talk by using an image-processing manner in the conventional art. Through the image processing manner, the left and right eye images 100 and 102 are displayed as compensation images 108 and 110. In this manner, due to the residual images, the cross-talk phenomenon is eliminated in the pre-processed compensation image 108, and thus the residual image of the left eye does not exist.
However, the disadvantage of the above technology lies in greatly reducing the single eye image contrast intensity. Therefore, other different solutions for eliminating the cross-talk phenomenon have been continuously researched.